Washington -LRB- CNN -RRB- -- The Syrian regime this week fired at least two Iranian-made , short-range ballistic missiles in what appears to be an effort to more precisely target Syrian rebels , two U.S. military officials tell CNN .

The Fateh A-110 missiles are more accurate than the older Scud variants that Syrian government forces have used in recent weeks .

Read more : NATO : Syrian forces firing more Scud missiles

The U.S. military officials declined to be identified because of the sensitive nature of the information . The Iranian government has not commented on the issue .

The Fateh trades range for accuracy . It can travel about 125 miles , while the Scud can go about 185 miles . But the Fateh has a `` circular error probable '' or -- CEP -- of 330 feet , while the Scud 's CEP is 1,480 feet . CEP is defined as the radius of a circle in which half of a missile 's lethal payload falls and is the standard measure of a missile 's accuracy .

The firings did not reach near Syria 's Turkish border . But the regime 's use of ballistic missiles is the reason NATO is planning to send U.S. , German and Dutch Patriot missile batteries to Turkish military installations : to protect the southern regions of that NATO ally . All six Patriot batteries are expected to be in place by the end of January .

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A NATO official could not confirm the use of short-range ballistic missiles this week , but NATO did detect the launch of such missiles inside Syria on a few December days , more recently on the 22nd .

`` The fact that Scud-type missiles were used in Syria emphasizes the need for effective defense protection of our ally Turkey , '' the NATO official said . `` This is why , earlier this month , NATO allies decided to deploy Patriot missiles in Turkey to augment Turkey 's air defenses . The deployment , which will start within weeks , is defensive only . Its aim is to deter any threats to and defend and protect the population and territory of Turkey . ''

U.S. officials say they believe the Syrians are firing ballistic missiles to preserve their aircraft , some of which have been shot down by rebels .

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Two U.S. military officials say the Syrian regime fired at least two Fateh A-110 missiles

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The move is an apparent attempt to more precisely target rebel forces , the officials say

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They decline to be identified because of the sensitive nature of the information

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The missiles are more accurate than older Scuds , which have a longer range